U.S. patent application number 10/255698 was filed with the patent office on 2003-04-03 for information processing unit and method for cooling same.
This patent application is currently assigned to NEC CORPORATION. Invention is credited to Kurihara, Kazuo.
Application Number | 20030063437 10/255698 |
Document ID | / |
Family ID | 19124190 |
Filed Date | 2003-04-03 |
United States Patent
Application |
20030063437 |
Kind Code |
A1 |
Kurihara, Kazuo |
April 3, 2003 |
Information processing unit and method for cooling same
Abstract
An information processing unit is provided in which, in a
suspension mode, a chip temperature does not exceed a temperature
specification, thus enabling unnecessary noise caused by a fan to
be avoided and, even if semiconductor chips of different types are
used, a common use of a motherboard can be achieved. When a
suspension signal output from a power supply controlling section to
control a supply power to be fed to a CPU is changed to a low
level, a fan controlling section outputs a fan controlling signal
adapted to lower a fan revolution speed to the fan.
Inventors: |
Kurihara, Kazuo; (Ohta-shi,
JP) |
Correspondence
Address: |
YOUNG & THOMPSON
745 SOUTH 23RD STREET 2ND FLOOR
ARLINGTON
VA
22202
|
Assignee: |
NEC CORPORATION
TOKYO
JP
|
Family ID: |
19124190 |
Appl. No.: |
10/255698 |
Filed: |
September 27, 2002 |
Current U.S.
Class: |
361/688 |
Current CPC
Class: |
H05K 7/20209 20130101;
G06F 1/206 20130101 |
Class at
Publication: |
361/688 |
International
Class: |
H05K 007/20 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 28, 2001 |
JP |
2001-304241 |
Claims
What is claimed is:
1. An information processing unit having at least one semiconductor
chip liberating a large amount of heat and being configured so as
to cool said semiconductor chip using a cooling unit, comprising: a
power source controlling section to output, when a change in supply
power to be fed to said semiconductor chip occurs, a supply power
changing signal; a cooling unit controlling section to output a
cooling unit controlling signal in response to said supply power
changing signal; and wherein, when said supply power changing
signal is input from said power source controlling section to said
cooling unit controlling section at a time of driving, said cooling
unit controlling section is configured so as to calibrate cooling
capability of said cooling unit.
2. The information processing unit according to claim 1, wherein
said semiconductor chip comprises a CPU (Central Processing unit
Unit).
3. The information processing unit according to claim 1, wherein
said power source controlling section outputs one signal making up
a binary signal as said signal showing a change in said amount of
said supply power while said information processing unit performs
an ordinary operation and outputs another signal making up said
binary signal when said information processing unit is switched
from its said ordinary operation to its power saving mode.
4. The information processing unit according to claim 1, wherein
said semiconductor chip is mounted in a socket on a common
motherboard in a manner so as to be attachable and detachable.
5. An information processing unit having at least one semiconductor
chip liberating a large amount of heat and being configured so as
to cool said semiconductor chip using a fan comprising: a power
source controlling section to output, when a change in supply power
to be fed to said semiconductor chip occurs, a supply power change
signal; a fan controlling section to output a fan controlling
signal in response to said supply power change signal; and wherein
said supply power change signal is input from said power source
controlling section to said fan controlling section at a time of
driving, said fan controlling section is configured so as to lower
a fan revolution speed.
6. The information processing unit according to claim 5, further
comprising a temperature monitoring section in which a plurality of
temperature threshold values corresponding to a characteristic of
each of semiconductor chips of two and more types is stored in
advance, and which is selectively set to a temperature threshold
value corresponding to the embedded semiconductor chip, when
arbitrary one semiconductor chip out of said semiconductor chips of
two or more types is embedded.
7. The information processing unit according to claim 5, wherein
said semiconductor chip comprises a CPU (Central Processing unit
Unit).
8. The information processing unit according to claim 5, wherein
said power source controlling section outputs one signal making up
a binary signal as said signal showing a change in said amount of
said supply power while said information processing unit performs
an ordinary operation and outputs another signal making up said
binary signal when said information processing unit is switched
from its said ordinary operation to its power saving mode.
9. The information processing unit according to claim 5, wherein
said semiconductor chip is mounted in a socket on a common
motherboard in a manner so as to be attachable and detachable.
10. The information processing unit according to claim 6, wherein
said temperature monitoring section includes a BIOS (Basic
Input/Output System) which stores in advance, a relative table
showing a relation between said semiconductor chip and said
temperature threshold value for every semiconductor chip of a
different type.
11. The information processing unit according to claim 8, wherein,
when one signal making up said binary signal is output as said
signal showing a change in said amount of said supply power from
said power source controlling section, said fan controlling section
outputs a fan controlling signal to lower a fan revolution
speed.
12. An information processing unit having at least one
semiconductor chip liberating a large amount of heat and being
configured so as to cool said semiconductor chip using a fan
comprising: a temperature monitoring section in which a plurality
of temperature threshold values corresponding to a characteristic
of each of semiconductor chips of two and more types is stored in
advance and which is selectively set to a temperature threshold
value, corresponding to the embedded semiconductor chip, when
arbitrary one semiconductor chip out of said semiconductor chips of
two or more types is embedded, and which outputs an alarm signal
when a temperature of said semiconductor chip exceeds said
temperature threshold value; a fan controlling section to output a
fan controlling signal in response to an alarm signal; and wherein,
when said alarm signal is input from said temperature monitoring
section to said fan controlling section at a time of driving, said
fan controlling section is configured so as to increase a fan
revolution speed.
13. The information processing unit according to claim 12, wherein
said semiconductor chip comprises a CPU (Central Processing unit
Unit).
14. The information processing unit according to claim 12, wherein
said temperature monitoring section includes a BIOS (Basic
Input/Output System) which stores in advance, a relative table
showing a relation between said semiconductor chip and said
temperature threshold value for every semiconductor chip of a
different type.
15. The information processing unit according to claim 12, wherein
said semiconductor chip is mounted on a socket on a common
motherboard in a manner so as to be attachable and detachable.
16. The information processing unit according to claim 14, wherein,
when one signal making up said binary signal is output as said
signal showing a change in said amount of said supply power from
said power source controlling section, said fan controlling section
outputs a fan controlling signal to lower a fan revolution
speed.
17. An information processing unit having at least one
semiconductor chip liberating a large amount of heat and being
configured so as to cool said semiconductor chip using a fan
comprising: a power source section to feed supply power to said
information processing unit; a fan controlling section to detect a
change in fed amounts of said supply power and, based on a result
from the detection, to output a fan controlling signal; and
wherein, when a signal showing a change in said fed amounts of said
supply power is input from said power source section to said fan
controlling section at a time of driving, said fan controlling
section is configured so as to lower a fan revolution speed.
18. The information processing unit according to claim 17, wherein
said semiconductor chip comprises a CPU (Central Processing unit
Unit).
19. The information processing unit according to claim 17, wherein
said semiconductor chip is mounted on a socket on a common
motherboard in a manner so as to be attachable and detachable.
20. A method for cooling an information processing unit having at
least one semiconductor chip liberating a large amount of heat
comprising: a step of outputting a supply power changing signal
from a power source controlling section to a cooling unit
controlling section when supply power to be fed to said
semiconductor chip is changed; a step of calibrating cooling
capability of a cooling unit by using said cooling unit controlling
section when said supply power changing signal is input from said
power source controlling section to said cooling unit controlling
section at a time of driving.
21. A method for cooling an information processing unit having at
least one semiconductor chip liberating a large amount of heat
comprising: a step of outputting a supply power changing signal
from a power source controlling section to a fan controlling
section when supply power to be fed to said semiconductor chip is
changed; and a step of lowering a fan revolution speed using said
fan controlling section when said supply power changing signal is
input from said power source controlling section to said fan
controlling section at a time of driving.
22. A method for cooling an information processing unit having at
least one semiconductor chip liberating a large amount of heat
comprising: a step of storing in advance a plurality of temperature
threshold values corresponding to a characteristic of each of
semiconductor chips of two or more types and, when arbitrary one
semiconductor out of semiconductors of two or more types is
embedded, of setting selectively said temperature threshold value
to a temperature threshold value corresponding to said embedded
semiconductor chip; a step of outputting an alarm signal from a
temperature monitoring section to a fan controlling section when a
temperature of said semiconductor chip exceeds said temperature
threshold value; and a step of increasing a fan revolution speed
using said fan controlling section when said alarm signal is input
from said temperature monitoring section to said fan controlling
section at a time of driving.
23. A method for cooling an information processing unit having at
least one semiconductor chip liberating a large amount of heat
comprising: a step of outputting a signal showing a change in
amounts of supply power from a power source section to feed supply
power to said information processing unit to a fan controlling
section; and a step of lowering a fan revolution speed using said
fan controlling section when said signal showing a change in said
amount of said supply power is input from said power source section
to said fan controlling section at a time of driving.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an information processing
unit and a method for cooling the same and more particularly to the
information processing unit configured so as to provide cooling for
a semiconductor chip liberating large amounts of heat and the
method for cooling the above information processing unit.
[0003] The present application claims priority of Japanese Patent
Application No. 2001-304241 filed on Sep. 28, 2001, which is hereby
incorporated by reference.
[0004] 2. Description of the Related Art
[0005] A Personal Computer known as a representative example of an
information processing unit is constructed by using a semiconductor
chip such as a CPU (Central Processing Unit), semiconductor memory,
or a like, as main components, however, heat is liberated, during
operations of the personal computer, from many components including
such the semiconductor chip. In particular, in the CPU serving as a
central component to perform a function of an arithmetic operation
in the personal computer, since its function is dramatically
improved in response to a demand for a high processing capability
required in recently available personal computers, amounts of
arithmetic operations per unit time are increasing. As a result, an
amount of heat liberated from the semiconductor chip making up the
CPU further increases greatly.
[0006] As an amount of heat liberated from such the semiconductor
chip increases, since a temperature (that is, a chip temperature)
rises, operations of the CPU become unstable as the temperature
rises and are put into a suspension state and, in the extreme, in
some cases, the semiconductor chip itself is thermally broken. To
solve this problem, conventionally, by mounting a cooling device
(cooling means) such as a heat sink, fan, or a like on the
semiconductor chip in order to inhibit a rise in a chip
temperature, special consideration is given so that operations of
the CPU are stabilized.
[0007] FIG. 6 is a plan view schematically showing an example of a
configuration with a CPU 52 making up a conventional personal
computer being mounted in an information processing unit. In the
personal computer (not shown), as shown in FIG. 6, a CPU 52 made up
of semiconductor chips is mounted at a desired place in a
motherboard (wiring substrate) 51 on which many components (not
shown) are packaged and, on the CPU 52, a fan 53, together with a
heat sink (not shown), is mounted as a cooling means for cooling
the CPU 53. Moreover, beside or on the CPU 52 is mounted a
temperature sensor (not shown) to detect a temperature of a
semiconductor chip. By configuring as above, since, by having the
fan 53 rotate during operations of the personal computer to
forcedly blow air on the CPU 52, the CPU 52 can be cooled and,
therefore, it becomes possible to inhibit a rise in a chip
temperature of the CPU 52 thus to successfully stabilize operations
of the CPU 52.
[0008] Moreover, the personal computer is provided with a mode for
a power saving function called a "suspension mode" which can be
operated at a same time when a mode is being ordinarily used, in
which, when an input device (input unit) such as a keyboard, mouse,
or a like is not operated for a specified period of time, in order
to achieve reduction in power consumption, a supply of a signal to
peripheral devices such as a display, hard disk, or a like is
temporarily stopped and operations of the CPU 52 are suspended and
only minimal amounts of power required for starting smooth
operations when the personal computer is re-started are supplied to
the CPU 52. In such the suspension mode, since almost no
semiconductor chips making up the CPU 52 liberate heat, the fan is
kept in a suspension state.
[0009] As described above, there are some types of
recently-available CPUs having achieved high performance in which
power has to be supplied at all time though its power level is
lower when compared with a level of power being applied at time of
ordinary operations in order to have a specified function kept even
in a suspension mode. In personal computers using such the CPU,
since a semiconductor chip entails liberation of heat, as a natural
result, in a suspension mode though an amount of the liberated heat
is small when compared with an amount of liberated heat at a time
of ordinary operations, the semiconductor chip has to be cooled by
operations of a fan.
[0010] FIG. 7 is a timing chart explaining a method for cooling the
semiconductor chip making up the CPU employed in the conventional
personal computer (referred to as a "first conventional example")
by using a fan 53. As shown in FIG. 7, operation modes (time) are
plotted as abscissa and a temperature A and a fan revolution speed
B are plotted as ordinate. It is presumed that, at a time t0, a
driven personal computer is performing its ordinary operation (S0)
and a temperature of a semiconductor chip making up the CPU is set
at "T" and a revolution speed of the fan 53 is set to be high. In
this state, at subsequent time t1, when the operation mode of the
personal computer is switched to a suspension mode (S1), a power
saving function works and, as a result, the chip temperature T is
lowered gradually. However, the fan 53 is kept at a high revolution
speed as has been originally set.
[0011] Next, at a time t2, when the personal computer returns to
its ordinary operation (S0), the CPU 52 causes the chip temperature
T again to rise. At this point, the fan 53 is still kept at a high
revolution speed as has been originally set. Next, by continuing
the ordinary operation (S0), the chip temperature T still rises
and, at a time t3, the chip temperature T exceeds a temperature
threshold value Tt set in advance and the fan 53 is kept at the
high revolution speed. Next, at a time t4, when the mode of the
personal computer is switched again to the suspension mode (S1),
its power saving function works, thereby causing the chip
temperature T to be gradually lowered, however, the fan 53 is kept
at the high revolution speed.
[0012] On the other hand, another conventional personal computer is
proposed in which, when an operation mode of the personal computer
is switched from an ordinary mode to a suspension mode (S1), a
revolution speed of the fan 53 is switched from an intermediate
speed to a stop state (referred to as a "second conventional
example"). A method for providing cooling for the CPU 52 employed
in the second conventional example is explained by referring to a
timing chart shown in FIG. 8. As in the case shown in FIG. 7, it is
presumed that, at a time the t0, a driven personal computer is
performing its ordinary operation (S0) and a temperature of a
semiconductor chip is set at "T" and a revolution speed of the fan
is set to be intermediate. In this state, at subsequent time t1,
when a mode of the personal computer is switched to a suspension
mode (S1), a signal showing that the mode of the personal computer
has been switched to the suspension mode (S1) by a temperature
sensor (not shown) is output to a control section (not shown) by
which a judgement is made in which cooling by the fan 53 is not
required and by which the control section exerts control so that a
revolution speed of the fan 53 is switched from an intermediate
speed to a stop state. As a result, a chip temperature T gradually
rises.
[0013] Next, at a time t2, when operation returns to the ordinary
operation (S0), a detection that the CPU 52 has started its
operations is made and the control section exerts control so that a
revolution speed of the fan 53 is switched from its stop state to
its intermediate state. As a result, a rise in the chip temperature
T is inhibited. Next, if the chip temperature T further rises by
continuing the ordinary operation (S0) and, at a time t3, the chip
temperature T exceeds a temperature threshold value Tt which is
preliminarily set, the control section detects this state and
switches the fan revolution speed from its intermediate speed to
its high speed.
[0014] Next, at a time t4, when the mode of the personal computer
is switched to its suspension mode (S1), a judgement is made that
cooling by the fan 53 is not required and the control section
exerts control so that a revolution speed of the fan 53 is switched
from its intermediate speed to its stop state. As a result, the
chip temperature T rises gradually and exceeds a temperature set in
advance in accordance with a temperature specification Td.
[0015] In the conventional information processing unit, since a
semiconductor chip which requires a supply of power even in a
suspension mode is used, cooling on the semiconductor chip
liberating heat even in the suspension mode (S1) is needed.
Therefore, following problems arise.
[0016] That is, in the conventional first example shown in FIG. 7,
at a time t1 or t4, even after the personal computer has been
switched from its ordinary operation (S0) to a suspension mode
(S1), since the fan 53 is kept at a high revolution speed that has
been originally set, unnecessary noises caused by the fan 53 occur.
That is, in the suspension mode, since the fan 53 is not operated
at a most suitable revolution speed to respond to heat liberation
of the semiconductor chip, it is impossible to avoid occurrence of
unnecessary noises caused by the fan 53. As a result, since a user
hears a large noise even in a suspension mode, he/she has a feeling
of anxiety or confusion as to whether or not the personal computer
is normally operating.
[0017] Next, in the second conventional example shown in FIG. 8, at
a time t1 and t4, when the personal computer is switched from its
ordinary operation (S0) to a suspension mode (S1), since an
operation of the fan 53 is stopped, unlike in the case of the first
conventional example, the occurrence of unnecessary noises caused
by the fan 53 can be avoided.
[0018] However, in the second conventional example, when the
personal computer is switched from its ordinary operation (S0) to
the suspension mode (S1), since a revolution speed of the fan 53
has been switched from its high speed to a stop state, cooling by
the fan 53 is not performed and therefore the chip temperature T
exceeds the temperature specification Td. As a result, it is made
difficult to stabilize operations of the CPU 52.
[0019] To avoid such the occurrence of unnecessary noises caused by
the fan 53, technology can be used which exerts control on the fan
53 revolution speed according to a rise and a fall in the chip
temperature T by monitoring the chip temperature T using software.
However, in this case, since a memory, arithmetic calculation
circuit, control circuit, power source, or a like are required, the
technology does not serve a purpose of the suspension mode, that
is, a purpose of a power savings. Moreover, an increase in an
amount of liberated heat caused by an operation of the software
occurs.
[0020] Moreover, limitations of heat resistance in the CPU 52 being
employed in the personal computer differ depending on a
characteristic of each kind of CPUs. That is, since the
characteristic of each CPU 52 is different from each other, timing
with which a revolution speed of the fan 53 is switched (to a high,
intermediate, or low speed) and the temperature threshold value Tt
differ in every type of the CPU 52. In this regard, conventionally,
since the temperature threshold value Tt of the CPU 52 to be
attached is designed in every motherboard 51, it is not possible to
obtain a common standard of the motherboard 51 for the CPU 52 of a
different kind. For example, if the CPU 52 having a high
heat-resistance is mounted on the motherboard 51 designed so that
the CPU 52 having a low temperature threshold value is to be
placed, since the fan 53 starts operation at a time of a low chip
temperature, noises from the fan 53 occur at an early stage.
[0021] In this case, the CPU 52 having a high heat-resistance has
to be mounted on a motherboard 51 designed so that the CPU 52
having a high temperature threshold value is to be placed. As a
result, a plurality of types of the motherboards 51 depending on a
type of the CPU 52 has to be prepared, thus causing an increase in
costs.
SUMMARY OF THE INVENTION
[0022] In view of the above, it is an object of the present
invention to provide an information processing unit which is
capable of preventing a chip temperature from exceeding a
temperature set in accordance with a specification and of avoiding
occurrence of unnecessary noises caused by a fan and of achieving
shared use of a motherboard even when semiconductor chips of
various kinds are used and a method for cooling the information
processing unit.
[0023] According to a first aspect of the present invention, there
is provided an information processing unit having at least one
semiconductor chip liberating a large amount of heat and being
configured so as to cool the semiconductor chip using a cooling
unit, including:
[0024] a power source controlling section to output, when a change
in supply power to be fed to the semiconductor chip occurs, a
supply power changing signal;
[0025] a cooling unit controlling section to output a cooling unit
controlling signal in response to the supply power changing signal;
and
[0026] wherein, when the supply power changing signal is input from
the power source controlling section to the cooling unit
controlling section at a time of driving, the cooling unit
controlling section is configured so as to calibrate cooling
capability of the cooling unit.
[0027] According to a second aspect of the present invention, there
is provided an information processing unit having at least one
semiconductor chip liberating a large amount of heat and being
configured so as to cool the semiconductor chip using a cooling
unit including:
[0028] a power source controlling section to output, when a change
in supply power to be fed to the semiconductor chip occurs, a
supply power change signal;
[0029] a fan controlling section to output a fan controlling signal
according to the supply power change signal; and
[0030] wherein the supply power change signal is input from the
power source controlling section to the fan controlling section at
a time of driving, the fan controlling section is configured so as
to lower a fan revolution speed.
[0031] In the foregoing, a preferable mode is one that wherein
includes a temperature monitoring section in which a plurality of
temperature threshold values corresponding to a characteristic of
each of semiconductor chips of two and more types is stored in
advance, and which is selectively set to a temperature threshold
value corresponding to the embedded semiconductor chip, when
arbitrary one semiconductor chip out of semiconductor chips of two
or more types is embedded.
[0032] According to a third aspect of the present invention, there
is provided an information processing unit having at least one
semiconductor chip liberating a large amount of heat and being
configured so as to cool the semiconductor chip using a fan
including:
[0033] a temperature monitoring section in which a plurality of
temperature threshold value corresponding to a characteristic of
each of semiconductor chips of two and more types is stored in
advance, and which the temperature threshold value is set
selectively to a temperature threshold value corresponding to the
embedded semiconductor chip, when arbitrary one semiconductor chip
out of the semiconductor chips of two or more types is embedded,
and which outputs an alarm signal when the temperature of the
semiconductor chip exceeds the temperature threshold value;
[0034] a fan controlling section to output a fan controlling signal
in response to an alarm signal; and
[0035] wherein, when the alarm signal is input from the temperature
monitoring section to the fan controlling section at a time of
driving, the fan controlling section is configured so as to
increase a fan revolution speed.
[0036] According to a fourth aspect of the present invention, there
is provided an information processing unit having at least one
semiconductor chip liberating a large amount of heat and being
configured so as to cool the semiconductor chip using a fan
including:
[0037] a power source section to feed supply power to the
information processing unit;
[0038] a fan controlling section to detect a change in fed amounts
of the supply power and, based on a result from the detection, to
output a fan controlling signal; and
[0039] wherein, when a signal showing a change in the fed amounts
of the supply power is input from the power source section to the
fan controlling section at a time of driving, the fan controlling
section is configured so as to lower a fan revolution speed.
[0040] In the foregoing, a preferable mode is one wherein the
semiconductor chip is made up of a CPU (Central Processing unit
Unit).
[0041] Also, a preferable mode is one wherein the power source
controlling section outputs one signal making up a binary signal as
the signal showing a change in the amount of the supply power while
the information processing unit performs an ordinary operation and
outputs another signal making up the binary signal when the
information processing unit is switched from its ordinary operation
mode to its power saving mode.
[0042] Also, a preferable mode is one wherein the temperature
monitoring section includes a BIOS (Basic Input/Output System)
which stores in advance, a relative table showing a relation
between the semiconductor chip and the temperature threshold value
for every semiconductor chip of a different type.
[0043] Also, a preferable mode is one wherein, when one signal
making up the binary signal is output as the signal showing a
change in the amount of the supply power from the power source
controlling section, the fan controlling section outputs a fan
controlling signal to lower a fan revolution speed.
[0044] Also, a preferable mode is one wherein, wherein the
semiconductor chip is mounted in a socket on a common motherboard
in a manner so as to be attachable and detachable.
[0045] According to a fifth aspect of the present invention, there
is provided a method for cooling an information processing unit
having at least one semiconductor chip liberating a large amount of
heat including:
[0046] a step of outputting a supply power changing signal from a
power source controlling section to a cooling unit controlling
section when supply power to be fed to the semiconductor chip is
changed;
[0047] a step of calibrating cooling capability of a cooling unit
by using the cooling unit controlling section when the supply power
changing signal is input from the power source controlling section
to the cooling unit controlling section at a time of driving.
[0048] According to a sixth aspect of the present invention, there
is provided a method for cooling an information processing unit
having at least one semiconductor chip liberating a large amount of
heat including:
[0049] a step of outputting a supply power changing signal from a
power source controlling section to a fan controlling section when
supply power to be fed to the semiconductor chip is changed;
and
[0050] a step of lowering a fan revolution speed using the fan
controlling section when the supply power changing signal is input
from the power source controlling section to the fan controlling
section at a time of driving.
[0051] According to a seventh aspect of the present invention,
there is provided a method for cooling an information processing
unit having at least one semiconductor chip liberating a large
amount of heat including:
[0052] a step of storing in advance a plurality of temperature
threshold values corresponding to a characteristic of each of
semiconductor chips of two or more types and, when arbitrary one
semiconductor chip out of semiconductor chips of two or more types
is embedded, of setting selectively the temperature threshold value
to a temperature threshold value corresponding to the embedded
semiconductor chip;
[0053] a step of outputting an alarm signal from a temperature
monitoring section to a fan controlling section when a temperature
of the semiconductor chip exceeds the temperature threshold value;
and
[0054] a step of increasing a fan revolution speed using the fan
controlling section when the alarm signal is input from the
temperature monitoring section to the fan controlling section at a
time of driving.
[0055] According to a eighth aspect of the present invention, there
is provided a method for cooling an information processing unit
having at least one semiconductor chip liberating a large amount of
heat including:
[0056] a step of outputting a signal showing a change in amounts of
supply power from a power source section to feed supply power to
the information processing unit to a fan controlling section;
and
[0057] a step of lowering a fan revolution speed using the fan
controlling section when the signal showing a change in the amount
of the supply power is input from the power source section to the
fan controlling section at a time of driving.
[0058] With the above configuration, when a change occurs in a
supply power to be fed to a semiconductor liberating a large amount
of heat, since the fan controlling section outputs a fan
controlling signal adapted to lower a fan revolution speed, even if
a mode of the information processing unit is switched to the
suspension mode, occurrence of noise caused by the fan can be
inhibited.
[0059] Moreover, when an information processing unit is switched
from its normal operation mode to its suspension mode, since a fan
revolution speed is not switched from its high speed state to a
stopped state, cooling using the fan can be achieved.
[0060] Furthermore, since at least one semiconductor chip
liberating a large amount of heat is constructed so as to be
attachable and detachable to a socket mounted on a motherboard,
semiconductor chips of different types can be attached to a common
motherboard. Therefore, in the suspension mode, a chip temperature
does not exceed a temperature specification, which enables
unnecessary noise caused by the fan to be avoided and even if
semiconductor chips of different types are used, a common use of
the motherboard can be achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0061] The above and other objects, advantages, and features of the
present invention will be more apparent from the following
description taken in conjunction with the accompanying drawings in
which:
[0062] FIG. 1 is a schematic block diagram showing configurations
of an information processing unit according to a first embodiment
of the present invention;
[0063] FIG. 2 is a diagram for showing a suspension signal output
from a power source controlling section in the information
processing unit according to the first embodiment of the present
invention;
[0064] FIG. 3 is a diagram for showing a temperature threshold
value set, depending on a type of a CPU, to a temperature
monitoring section of the information processing unit according to
the first embodiment of the present invention;
[0065] FIG. 4 is a diagram for showing a fan controlling signal
output from a fan controlling section in the information processing
unit according to the first embodiment of the present
invention;
[0066] FIG. 5 is a timing chart for explaining a method for cooling
a CPU in the information processing unit by using a fan according
to the first embodiment of the present invention;
[0067] FIG. 6 is a plan view schematically showing a configuration
with a CPU making up a conventional personal computer being mounted
in an information processing unit;
[0068] FIG. 7 is a timing chart explaining a method for providing
cooling for the CPU employed in the conventional information
processing unit (first conventional example) using a fan; and
[0069] FIG. 8 is a timing chart for explaining an other method for
providing cooling for the CPU employed in the conventional
information processing unit (second conventional example) using the
fan.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0070] Best modes of carrying out the present invention will be
described in further detail using various embodiments with
reference to the accompanying drawings.
First Embodiment
[0071] FIG. 1 is a schematic block diagram showing configurations
of an information processing unit according to a first embodiment
of the present invention. FIG. 2 is a diagram showing a suspension
signal output from a power source controlling section in the
information processing unit according to the first embodiment. FIG.
3 is a diagram showing a temperature threshold value set, depending
on a type of a CPU, to a temperature monitoring section of the
information processing unit according to the first embodiment. FIG.
4 is a fan controlling voltage from a fan controlling section 4 in
the information processing unit according to the first embodiment.
FIG. 5 is a timing chart explaining a method for cooling a CPU in
the information processing unit according to the first embodiment.
Moreover, in the embodiment, the information processing unit is
applied to a personal computer.
[0072] An information processing unit (personal computer) 6, as
shown in FIG. 1, includes a CPU 1 made up of semiconductor chips
serving as a central component having an arithmetic operating
function for the personal computer, a temperature monitoring
section 2 into which a temperature signal St indicating a chip
temperature detected by a temperature sensor (not shown) mounted on
the CPU 1 is input and from which an alarm signal Sa is output
depending on the temperature signal St when an embedded
semiconductor chip exceeds a temperature threshold value, a power
source controlling section 3 which controls supply power to be fed
to the CPU 1 and outputs a suspension signal (supply power changing
signal) Ss, the fan controlling section 4 which outputs a fan
controlling signal Sf depending on an output signal fed from the
temperature monitoring section 2 or a suspension signal Ss fed from
the power source controlling section 3, and a fan 5 a revolution
speed of which is controlled by the fan controlling signal Sf.
[0073] Moreover, the temperature monitoring section 2 stores, in
advance, a plurality of temperature threshold values corresponding
to a characteristic of each of the semiconductor chips of two or
more types and, when one arbitrary semiconductor chip out of the
semiconductor chips of the two or more types is embedded, sets
selectively the temperature threshold value to a temperature
threshold value corresponding to the embedded semiconductor chip
and outputs the alarm signal Sa when a temperature of the
semiconductor chip exceeds its temperature threshold value.
[0074] The suspension signal Ss output from the power source
controlling section 3, as shown in FIG. 2, is output, while the
personal computer is performing an ordinary operation, an H (high)
level signal and is also output, when the personal computer
switches its operation mode from its ordinary operation to its
suspension mode, an L (low) level signal. Therefore, by confirming
a level of the suspension signal Ss using the fan controlling
section 4, whether or not the personal computer is performing its
ordinary operation or whether or not the personal computer switches
its mode from its ordinary operation to its suspension mode can be
checked.
[0075] In the temperature monitoring section 2, as shown in FIG. 3,
a plurality of temperature threshold values corresponding to a
characteristic of each of the semiconductor chips of various types,
for example, temperature threshold values for every CPU operating
in accordance with a different temperature specification (that is,
a characteristic), is stored in advance. For example, in the case
of a CPU-A operating in accordance with a temperature specification
being as relatively high as 73.degree. C., a temperature
specification being as relatively high as 70.degree. C. is set as a
temperature threshold value. On the other hand, for example, in the
case of a CPU-B operating in accordance with a temperature
specification being relatively low as 65.degree. C., a temperature
specification being as relatively low as 63.degree. C. is set as a
temperature threshold value. Specifically, a relative table showing
a relation between the semiconductor chip and the temperature
threshold value for every semiconductor chip having a different
type is stored in a BIOS (Basic Input Output System). This enables
an adjustment of timing with which a fan revolution speed (high,
intermediate, or low speed) can be switched depending on a
temperature specification of a CPU being used in the personal
computer, that is, on a limitation of heat resistance. The CPU 1 is
so configured as to be detachable and attachable from and to a
socket mounted on a motherboard of the personal computer. This
allows even a CPU of a different type to be attachable to a common
motherboard. As a result, preparation of motherboards of a
plurality of kinds depending on a kind of the CPU is not
necessary.
[0076] The fan controlling signal Sf output from the fan
controlling section 4, as shown in FIG. 4, is so configured to make
a fan controlling voltage being different depending on a chip
temperature of a detected CPU 1 be output to the fan 5 and a fan
revolution speed to be changed at a time of operations of the fan 5
so that cooling capability is calibrated at every occasion. For
example, when a chip temperature being relatively low is detected,
control is exerted so that a fan controlling voltage being as
relatively low as 6V is output as the fan controlling signal Sf to
the fan 5 and a revolution speed of the fan 5 is changed to be 1500
rpm (low speed) so as to lower a cooling capability of the fan 5.
Moreover, when a chip temperature being relatively high is
detected, control is exerted so that a fan controlling voltage
being as relatively high as 12V is output as the fan controlling
signal Sf to the fan 5 and a revolution speed of the fan 5 is
changed to be 2200 rpm (high speed) so as to increase cooling
capability of the fan 5. Furthermore, when a chip temperature being
relatively intermediate is detected, control is exerted so that a
fan controlling voltage being as relatively intermediate as 8V is
output as the fan controlling signal Sf to the fan 5 and a
revolution speed of the fan 5 is changed to be 1800 rpm
(intermediate speed) so as to calibrate a cooling capability of the
fan 5 to be operated at an intermediate level.
[0077] Next, a method for cooling a semiconductor chip making up a
CPU 1 in the personal computer using the fan 5 will be described by
referring to FIG. 5. Here, one example using a CPU-A shown in FIG.
3 as the CPU 1 shown in FIG. 1 is described. In FIG. 5, an
operation mode (time) is plotted as abscissa and a temperature A
and a fan revolution speed B as ordinate. A temperature threshold
value Tt being 70.degree. C. corresponding to 73.degree. C. being a
temperature specification in the CPU-A shown in FIG. 3 is set in
advance in the temperature monitoring section 2. In FIG. 5, at a
time t0, when the personal computer is performing an ordinary
operation (S0), a chip temperature T of a semiconductor chip (in
the example, CPU-A) making up the CPU 1 is set to be lower than a
temperature specification 73.degree. C. and the fan controlling
section 4 outputs a fan controlling voltage being 8V to the fan 5
as the fan controlling signal Sf and a revolution speed of a fan is
set to be at an intermediate speed of 1800 rpm. The revolution
speed of the fan 5 is made changeable, if necessary, depending on a
performance of the CPU 1. In this state, the suspension signal Ss
output from the power controlling section 3 is at the H (high)
level in FIG. 2.
[0078] Next, at a time t1, when the personal computer is switched
to a suspension mode (S1), a power saving function works and the
chip temperature T gradually is lowered and the suspension signal
Ss output from the power controlling section 3 is changed to be at
the L (low) level. The fan controlling section 4, based on the L
level signal, outputs a fan controlling voltage being 6V to the fan
5 as the fan controlling signal Sf and the revolution speed of the
fan 5 is set to be at the low speed of 1500 rpm. As a result,
cooling capability using the fan 5 is lowered.
[0079] Thus, according to the example, by confirming the suspension
signal Ss output from the power controlling section 3 using the fan
controlling section 4, at the time t1, when a level of its output
is changed to be at the L (low) level, since the fan controlling
section 4 outputs the fan controlling signal Sf used to lower a fan
revolution speed to the fan 5, when the personal computer is
switched to a suspension mode, it is possible to avoid unnecessary
noise caused by the fan 5.
[0080] Next, at a time t2, when the personal computer is returned
to an ordinary operation (S0), the operation of the CPU 1 causes
the chip temperature T to rise again. A suspension signal Ss output
from the power source controlling section 3 is changed to be at the
H (high) level, since the temperature signal St showing a rise in
the temperature is output from the temperature sensor (not shown)
mounted in the CPU 1 to the temperature monitoring section 2, the
temperature monitoring section 2 outputs an alarm signal Sa
depending on the temperature signal St. In response to this signal,
the fan controlling section 4 outputs a fan controlling voltage of
8V to the fan 5 as the fan controlling signal Sf and a revolution
speed of the fan 5 is set to be at an intermediate speed of 1800
rmp. As a result, since cooling capability using the fan 5
increases, a rise in the chip temperature T of the CPU 1 is
inhibited.
[0081] Next, personal computer's continuation of the ordinary
operation (S0) causes the chip temperature T to further rise and,
at a time t3, when the chip temperature T exceeds a temperature
threshold value 70.degree. C. set in advance, since a temperature
signal St showing a rise in the chip temperature T is output to the
temperature monitoring section 2 from a temperature sensor mounted
in the CPU 1, the temperature monitoring section 2 outputs the
alarm signal Sa in response to its temperature signal St. This
indicates that a chip temperature T of the semiconductor chip comes
near to a temperature specification Td. Based on this, the fan
controlling section 4 outputs a fan controlling voltage of 12V as
the fan controlling signal Sf and the revolution speed of the fan 5
is set to be at a high speed of 2200 rmp. As a result, since
cooling capability further increases, a rise in the chip
temperature T in the CPU 1 is inhibited.
[0082] Next, at a time t4, when the personal computer is switched
to the suspension mode (S1), a power saving function works and the
chip temperature T gradually is lowered and the suspension signal
Ss output from the power source controlling section 3 is changed to
be at the L (low) level. The fan controlling section 4, based on
the L level signal, outputs a fan controlling voltage of 6V to the
fan 5 as the fan controlling signal Sf and the revolution speed of
the fan 5 is set to be at a low speed of 1500 rmp. As a result,
cooling capability of the fan 5 is lowered.
[0083] Thus, according to the embodiment, by confirming the
suspension signal Ss output from the power source controlling
section 3 using the fan controlling section 4, at the time t4, when
its output level is changed to be at the L level, since the fan
controlling section 4 outputs the fan controlling signal Sf used to
lower the fan revolution speed to the fan 5, when the personal
computer is switched to a suspension mode (S1), occurrence of
unnecessary noise caused by the fan 5 can be avoided. Therefore,
there is neither anxiety nor confusion to users.
[0084] Next, when a CPU-B shown in FIG. 3 is used as the CPU 1
shown in FIG. 1, after the temperature threshold value Tt of
63.degree. C. corresponding to the temperature specification of
65.degree. C. has been stored in advance in the temperature
controlling section 2, even when same cooling method as in the case
of using the CPU-A, as the CPU 1, is used. In this case, in FIG. 5,
at the time t1 and thereafter, personal computer's continuation of
the ordinary operation (S0) causes the chip temperature T to
further rise and, at the time t3, when the chip temperature T
exceeds the temperature threshold value of 63.degree. C. set in
advance, a temperature signal St indicating a rise in a chip
temperature T is output from the temperature sensor mounted in the
CPU 1 to the temperature monitoring section 2, the temperature
monitoring section 2 outputs the alarm signal Sa depending on the
temperature signal St. Based on this, the fan controlling section 4
outputs the fan controlling voltage of 12V to the fan 5 as the fan
controlling signal Sf and the revolution speed of the fan 5 is set
to be at 2200 rmp. As a result, cooling capability by the fan 5
further increases, a rise in the chip temperature T of the CPU 1 is
inhibited.
[0085] Except the above, almost the same operations as performed in
a case in which the CPU-A is used are performed. Therefore, when a
suspension signal Ss output from the power controlling section 3 is
changed to be at the L level at the time t1 and t4, since a fan
controlling signal Sf used to lower a revolution speed of the fan 5
is output by the fan controlling section 4, when the personal
computer is changed to be a suspension mode (S1), unnecessary noise
caused by the fan 5 can be avoided.
[0086] As described above, according to the information processing
unit 6 of the embodiment, after the suspension signal Ss output
from the power source controlling section 3 to control supply power
fed to the CPU 1 is confirmed, when a change in the supply power
occurs and its output is changed to be the L level, the fan
controlling section 4 outputs a fan controlling signal Sf used to
lower a fan revolution speed to the fan 5, when the personal
computer is switched to the suspension mode (S1), unnecessary noise
caused by the fan 5 can be avoided. Therefore, as in the case of
the first conventional example, when the personal computer is
switched from its ordinary operation (S0) to its suspension mode
(S1), the fan revolution speed is kept at the high speed set
originally, which stops occurrence of unnecessary noise caused by
the fan 5.
[0087] Moreover, according to the information processing unit 6 of
the embodiment, at the time t0 and Lime t4, when a change in the
supply power occurs and a suspension signal Ss is changed to be at
the L level, the fan controlling section 4 outputs the fan
controlling signal Sf used to lower the fan revolution speed to the
fan 5. However, as in the case of the second conventional example,
at the time t1 and t4, when the personal computer is changed from
its ordinary operation (S0) to its suspension mode (S1), since a
fan revolution speed is not changed from a high speed to a stopped
state to avoid unnecessary noise caused by the fan 5, cooling using
the fan 5 is not performed thus there occurs no case in which a
chip temperature T exceeds a temperature specification Td.
[0088] Moreover, according to the information processing unit 6 of
the embodiment, the CPU 1 is constructed in a manner so as to be
attachable and detachable to a socket mounted in a motherboard, any
CPU being different in types can be attached to a common
motherboard and therefore preparation for a plurality of
motherboards depending on a type of the CPU 1 is not necessary. As
a result, reduction in costs is made possible.
[0089] As described above, as shown in FIG. 3, by setting, in
advance, a relative table for every CPU 1 being different in types,
that is, being different in temperature specifications to the
temperature monitoring section 2, effects described above can be
obtained in the case of using any kind of the CPU 1.
[0090] Thus, according to the information processing unit 6 of the
embodiment, when a suspension signal Ss output from the power
source controlling section 3 adapted to control supply power to be
fed to the CPU 1 is changed to be at the L level, since the fan
controlling section 4 outputs the fan controlling signal Sf used to
lower the revolution speed of the fan 5, when the personal computer
is switched to a suspension mode (S1), noise caused by the fan 5
can be inhibited. Moreover, according to the information processing
unit 6 of the embodiment, when the personal computer is switched
from its ordinary operation (S0) to a suspension mode (S1), since
the revolution speed of the fan 5 cannot be switched from a high
speed state to a stopped state, cooling using the fan 5 can be
performed.
[0091] Furthermore, according to the information processing unit 6
of the embodiment, the CPU 1 is constructed in a manner so as to be
attachable and detachable to a socket mounted in a motherboard, any
CPU being different in types can be attached to a common
motherboard and therefore preparation for a plurality of
motherboards depending on a type of the CPU is not necessary.
Therefore, in the suspension mode (S1), the chip temperature T does
not exceed a temperature specification and therefore unnecessary
noise caused by the fan 5 can avoided and a common use of a
motherboard using a semiconductor chip of a different type can be
made possible.
[0092] It is apparent that the present invention is not limited to
the above embodiments but may be changed and modified without
departing from the scope and spirit of the invention. For example,
the present invention is not limited to the fan 5 shown in the
embodiment. That is, so long as a degree (cooling capability) of
cooling the semiconductor chip can be calibrated, other cooling
means such as water, gas, or a like can be used. Moreover, in the
embodiment, an example is provided in which the fan controlling
signal Sf is output, in response to the suspension signal Ss output
from the power source controlling section 6, from the fan
controlling section 4, however, the fan controlling signal Sf is
not limited to such the suspension signal Ss. That is, a power
source controlling section 3 to feed supply power to the
information processing unit and the fan controlling section 4 used
to detect a change in an amount of the supply power and to output
the fan controlling signal Sf based on the change are provided.
According to the example, a purpose can be achieved without
outputting the suspension signal Ss being a special signal.
[0093] Moreover, in the embodiment, an example is provided in which
an information processing unit is applied to the personal computer
However, so long as a semiconductor chip liberating a large amount
of heat at a time of operation such as a CPU is used, the present
invention can be applied to an other information processing unit
such as PDA (Personal Digital Assistants).
[0094] As a semiconductor chip liberating a large amount of heat, a
semiconductor chip used in the CPU is employed in the embodiment,
however, a chip set controlling a signal or other semiconductor
chip being used for graphical drawing or a like can be applied. A
signal that can be used is not limited to a suspension signal Ss
output from the power source controlling section 3 so long as it is
a signal showing a change in the supply power and other signals can
be used. Moreover, the suspension signal Ss that can be used is not
limited to that used in the embodiment. A signal in which its
voltage is reversed between an H level and an L level, that is, a
binary signal having its H and L levels may be employed as the
suspension signal. Furthermore, in the embodiment, the value of
temperature specification and temperature threshold value of a CPU,
a fan control voltage, a fan revolution speed, or a like is
provided as one example and therefore these values may be changed
depending on a purpose, application or a like.
* * * * *